Modeling of visco-elastic supports for hydropower applications
2015 (English)In: Proceedings of the 9th IFToMM International Conference on Rotor Dynamics / [ed] Paolo Pennacchi, Encyclopedia of Global Archaeology/Springer Verlag, 2015, Vol. XVIII, 2189-2197 p.Conference paper (Refereed)
This paper presents a numerical model of how a visco-elastic support affects the dynamical response of a 42 MW Kaplan turbine that is experiencing resonance problems. The supports are placed between the bearing bracket and the supporting concrete structure. Since the supports are nonlinear, the nodal displacements are solved using a Runge-Kutta time integration method where the visco-elastic supports are implemented as a nonlinear force. To reduce calculation time the number of degrees of freedom of the rotor model is reduced using the Improved Reduction System. Excitation of the system is implemented as a stationary force in the runner with varying frequency. The resulting nodal displacement from the transient simulation is then compared to the system simulated without the supports to show how the machine dynamics are affected. The simulations show that the visco-elastic supports efficiently reduces the displacements in the lower vibration modes. The reduced vibration levels should decrease the probability of resonance problems occurring when running at operating speed.
Place, publisher, year, edition, pages
Encyclopedia of Global Archaeology/Springer Verlag, 2015. Vol. XVIII, 2189-2197 p.
Mechanisms and Machine Science, ISSN 2211-0984 ; 21
Research subject Computer Aided Design
IdentifiersURN: urn:nbn:se:ltu:diva-34368DOI: 10.1007/978-3-319-06590-8_180Local ID: 88b1ee7a-c5fb-4795-8426-df4b168ba494ISBN: 978-3-319-06589-2 (print)ISBN: 978-3-319-06590-8 (electronic)OAI: oai:DiVA.org:ltu-34368DiVA: diva2:1007618
IFToMM International Conference on Rotor Dynamics : 22/09/2014 - 25/09/2014
Validerad; 2015; Nivå 1; 20141118 (erisyn)2016-09-302016-09-30Bibliographically approved